Opis: Dielectric spectroscopy characterization of clay-water mixtures is presented and the obtained spectra are analysed. A theoretical model for ion dynamics isproposed in which motion of ions in pore space electrolyte is interrupted by trapping events at the mineral surfaces. The typical time scales for these processes are given in terms of the physical properties of the material. It isshown that the microscopic motion of the ions in a complex environment of clay-water system can be described with fractional dynamics leading to subdiffusive behavior. Ključne besede:soil mechanics, dielectric spectroscopy, porous material, conductivity, fractional dynamics Objavljeno: 18.05.2018; Ogledov: 457; Prenosov: 62 Celotno besedilo (105,00 KB) Gradivo ima več datotek! Več...

Opis: This paper describes an investigation into the properties of spatially embedded complex networks representing the porous architecture of soil systems. We suggest an approach to quantify the complexity of soil pore structure based on the node-node link correlation properties of the networks. We show that the complexity depends on the strength of spatial embedding of the network and that this is related to the transition from a non-compact to compact phase of the network. Ključne besede:soil complexity, soil pore networks, complex systems Objavljeno: 21.07.2017; Ogledov: 758; Prenosov: 259 Celotno besedilo (3,85 MB) Gradivo ima več datotek! Več...

Opis: This thesis seeks to establish the link between the structure (in a topological sense) of porous space and charged particle dynamics in porous matter, specifically in constituent elements of sustainable building materials such as clay, cement and soil. The work done is a combination of experimental research and modelling of analysed data using advanced and expanded network models to model pore structure and generalized conductivity model. The main outcome of this doctoral thesis is the demonstration that there is a correlation between the large scale structure of the pore space and the properties of the motion of charged particles through the pore space. This was achieved by conducting two experiments: the structure of pore space of selected porous materials (soil samples, clays, cements, clay-cement mixtures) was investigated using state-of-the-art X-ray computed microtomography, while the dynamics of charged particles in the samples was probed using low-frequency dielectric spectroscopy. The research done and described in the thesis is directed towards the advancement of understanding the transport phenomena and the structure of porous media which is of paramount importance for solving problems in building physics dealing with moist transport in building's envelope, the building-ground interaction, and in transport of contaminants in the vicinity of the repositories where the transfer of moist through soil can be the source of contamination. Ključne besede:porous matter, clay-water system, hydrating cement, fractional dynamics, dielectric response, X-ray computed tomography, image analysis, complex network Objavljeno: 11.05.2011; Ogledov: 3911; Prenosov: 183 Celotno besedilo (34,69 MB)